“Making a Sea-Doo go fast is very easy,” RIVA Racing’s Jesus Garcia grinned. “Sea-Doo makes it very easy to tune and get power out of. You will like it.” The affable Spanish-born Head of Engine Management Development is the newest member of RIVA’s legendary Research & Development team, flanked by South African-born Bruce Clarkson and red blooded-American Mark Nystrom (who I relentlessly tease about his ongoing vintage Ford Mustang. Car guys are wont to incessant harassment). Garcia, whose relentlessness in perfecting the several newly-added Performance Packages in RIVA’s roster, oversaw today’s testing session.
As Garcia pushed me off of the floating dock, its rubberized casters carrying the Inferno Red ’17 Sea-Doo RXP-X 300 into the water, waved happily flashing me a toothy grin. He knew something I didn’t. I just knew it. “Keep the VTS just one notch above bottom,” he suggested. Toggling down, I set the Variable Trim System as instructed and confirmed the iControl command, putting me into Sport mode. Much if not all of the modifications made to this Sea-Doo were to effectively unlock the 1,630cc 3-cylinder four-stroke, pushing its advertised 300-horsepower to a hair’s breadth above 350. Unlike any Sea-Doo I had ridden previous, this one’s engine carried an ungodly lope to the idle.
Performing my best Erminio Iantosca impression, I leaned low and deep over the handlebars and stabbed the throttle. Two or three recoils off of the preset rev limiter, and the RXP-X erupted past 6,000rpm. Seven thousand arrived nanoseconds later. Eight thousand followed. The iridescent red needle pegged at 9,000rpm and glued itself vertical. The sensation was violent. The treeline that once was perched on the horizon appeared in full detail almost instantaneously. I backed off of the throttle, listening to the supercharger scrub off boost. With so much power on tap, driver input felt insulated, muted. I wrenched the bars hard right and the howling Sea-Doo arched in that direction.
With so much thrust churning through the pump, the RXP-X remained planted, refusing to break free. The deep keel of the T3 hull split chop better with a handful of boosted horsepower than ever in stock trim. RIVA Racing’s IJSBA Limited Class Race Kit for the 2017 Sea-Doo RXP-X 300 is advertised at a maximum of 85mph @ 9,000rpm, but results may vary. “If it goes 88mph, I have them advertise 86 only because our conditions might be better (temperature of air/water, altitude, etc.) – and I don’t want them thinking we lied to them,” Garcia admitted. All of his speed testing is performed with 1/3 tank of fuel, which can also play a factor. Garcia wanted no confusion. That’s why our GPS reading of 85.9mph on our iPhone app was acceptable.
The newly minted IJSBA Limited Class Race Kit is without handling components, solely performance adders. As is with all packages, RIVA includes its RIVA MaptunerX BRP Bundle (PT# RS110SC-B) with the appropriate tune. Next come a Bosch VT1100 Fuel Injector Kit (PT# VT1100-INJK), RIVA Sea-Doo Rising Rate Fuel Pressure Regulator Kit – `08 & Newer (PT# RS12050-RRFPR-08), a RIVA Sea-Doo RXP/RXT 300 & GTX LTD 300 Power Filter (PT# RS13140-1), a RIVA Sea-Doo 4-TEC Catch Can/Engine Breather Kit (PT# RS19050-BCC-1), and a RIVA Sea-Doo RXP/RXT 300 Intake Manifold Upgrade Kit (PT# RS12140-IMUK). Obviously, a RIVA Valve Train Upgrade Kit – Seadoo 4TEC (PT# RS19050-VTU) is necessary with the RIVA Sea-Doo 300 XX Charger (PT# RS17140-135).
The big addition over the existing Stage 2 kit is the addition of RIVA’s Sea-Doo 300 Racing Camshaft (PT# RS19140-BCS), which pushes the Sea-Doo’s performance from a stellar 72mph at 8,000rpm to the above 85mph at 9,000rpm. Finalizing the rest of the package is a RIVA Sea-Doo 300 Open Loop Cooling Kit (PT# RS1013-140), a RIVA Sea-Doo RXP/RXT 300 Free Flow Exhaust Kit (PT# RS16140-1) and a specially-pitched Skat-Trak 3-Blade Swirl Impeller 15/19 (PT# SS618328SW15/19). Achieving such breakneck acceleration and reaching such speeds with so little invasive parts in regards to rebuilding the engine itself or replacing more than the prop is a testament both to Sea-Doo’s ever-evolving product and RIVA’s ability to magnify the abilities within the craft itself without having to re-engineer large portions of the machine.
All of this comes with a price, and that well beyond the kit’s listed MSRP of $5492.64. All pretenses of a civilized, refined and casual riding experience are gone with the fully-equipped RXP-X 300. As if given a large portion of Dr. Jekyll’s serum, the RIVA Racing IJSBA Limited Class Race Kit-equipped ’17 Sea-Doo RXP-X 300 is brutish, punishing and unrelenting. When unleashed by the vice of the throttle, the machine will challenge your mettle by pressing your body with g-forces never otherwise felt, both in the corners and in straight line acceleration. The surge of acceleration as it ascends the Everest-like slope of its power curve will attempt to peel your fingers from their clutches around the palm rest grips. Again, you’ve been warned – and more so than I ever was.